Answer:
A = $8406.6
Step-by-step explanation:
Given:
Average rate 
Initial cost of painting 
Time 
We need to find the final amount of painting at the end of a 20-year.
Solution:
Using Exponential Growth rate formula as:
----------(1)
Where:
A = Final amount
a = Initial amount.
r = Rate as a decimal.
t = Time.
Now, we substitute all given values in equation 1.


Substitute
in above equation.

A = $8406.62
Therefore, value of the painting at the end of a 20-year A = $8406.6
Answer:
Step-by-step explanation:
In a G.P, the nth term is given as
Un=ar^(n-1)
Where
a is first term
n is nth term
And r is common ratio
So in the question given above,
The third term exceed the first term by 16
i.e U3=U1+16
Where U1=a. First term
U3=a+16
Given also that, the sum if the third term and fourth term is 72.
Then U3+U4=72.
We are told to find common ratio (r)
U3=ar^3-1
U3=ar^2
Also, U4=ar^3
U3+U4=72
ar^2+ar^3=72
ar^2(1+r)=72. equation 1
Also for
U3=a+16
ar^2=a+16
ar^2-a=16
a(r^2-1)=16. From (x^2-y^2)=(x+y)(x-y)
Then,
a(r-1)(r+1)=16. Equation 2
Divide equation 2 by equation 1
a(r-1)(r+1)/ar^2(1+r) =16/72
Then a cancel a and (1+r) cancel (1+r)
So,
(r-1)/r^2=2/9
Cross multiply
9(r-1)=2r^2
2r^2-9r+9=0
Solving the quadratic equation
2r^2-6r-3r+9=0
2r(r-3)-3(r-3)=0
(r-3)(2r-3)=0
r-3=0. Or. 2r-3= 0
Then r=3 or r=3/2
Answer: 9. triangles measure to 180 degrees
10. 90 degrees
11. 180 degrees
12. angles that measure to 90 degrees
13. angles that measure to 180 degrees
14. 148 degrees
15. 68 degrees
1. a fraction that uses the longest length on a shape
2. 0.3125
3. 0.33333333333
4. 30
5. 0.25
6. 60
7. 15
8. 18
Step-by-step explanation:
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well, 1/7th of the cupcakes is 3. so 2/7ths makes 6. and 21 minus 6 is 15. So, your answer is 15.
it says if
ax^2+bx+c=0
a<0
answer is D because, there is (-) near of x^2